Evaluation Of Genetic Diversity In Wheat Genotypes (Triticum aestivum L.)

In any crop improvement program, the presence of genetic divergence is an important entry point for selection and hybridization. Genetic divergences were estimated using Mahalonobis D2-statistics and principal component analysis. A trial was executed using ninety wheat genotypes with the objective of determining the genetic divergence in wheat crop. The studies were carried out in during the rabi 2014-15 cropping season using a randomized complete block design with three replications. The genotypes were grouped into 10 clusters namely cluster I (34 genotypes), cluster II (44 genotypes), cluster III ( genotypes), cluster IV (1 genotype), cluster V (1 genotype) cluster VI (1 genotype) cluster VII (1 genotype) cluster VIII (4 genotypes) cluster IX (1 genotype) and cluster X (2 genotypes). This indicates that the genotypes grouped within a particular cluster are more or less genetically similar to each other and apparent wide diversity is mainly due to the remaining genotype distributed over rest of the other clusters. The maximum intra cluster distance exhibited for cluster VIII (124.718) and lowest for cluster VI (111.063). The maximum inter cluster distance was showed between cluster VI and I (649.474) whereas, minimum between clusters III and II (104.941). The hybridization between the genotypes HUW 658, K-9265 and PBW-533 with Unnat halna, HD2932 and DBW 16 would produce heterotic hybrids and wide spectrum of variability in subsequent generations. The grain yield per plant followed by plant height, spike length, days to maturity, number of tiller per plant, dry gluten content, number of spikelet per spike, biological yield per plant and days to 50% flowering contributed most towards genetic divergence.